There have been a lot of plans to limit the influence of wealthy donors in politics. Now a new super PAC called the Mayday PAC is trying something unusual - raising big money, then spending it to reduce the role of big money in political campaigns. Jacob Goldstein from our Planet Money team reports.

JACOB GOLDSTEIN, BYLINE: This morning, Jim Rubens woke up to some good news. The Mayday PAC announced it's going to spend millions of dollars on his behalf. Rubens lives in New Hampshire. He is an underdog in the state's Republican primary for a U.S. Senate seat. He supports more public financing in political campaigns, and he thinks super PACs have too much influence.

JIM RUBENS: I predicted at the very outset of this campaign between 70 and 85 percent of the money would be outside money.

GOLDSTEIN: I imagine you thought that money would be against you, not for you.

RUBENS: I did. (Laughing) I did. I clearly did.

GOLDSTEIN: The Mayday PAC's goal is to take candidates like Rubens - candidates who are behind in the polls or in close races - and make their support for changing campaign finance a central part of the election. The idea is to prove that this is an issue that can change the way people vote. In addition to Rubens, the Mayday PAC will support a Democratic candidate in an Iowa congressional race and three more candidates who they'll announce in the coming weeks. Lawrence Lessig, a Harvard law professor who's one of the group's founders, says, these five campaigns are really just an experiment. If the group succeeds this year, the big action will be in the next election cycle.

LAWRENCE LESSIG: In 2016, we want to raise a substantially larger amount of money - could be 200 million, could be 800 million - so that we can win a Congress committed to fundamental reform in the way campaigns are funded.

GOLDSTEIN: And, yes, there's something funny about spending hundreds of millions of dollars to reduce the influence of big money in politics. But Lessig basically says, get over it.

LESSIG: There's something ironic with that, you might think. But we need to embrace this irony and recognize that we need to use the system that exists to change the system.

GOLDSTEIN: The Mayday PAC was cofounded by Mark McKinnon, a political advisor who worked for George W. Bush, and one of its biggest donors is Peter Thiel, a libertarian tech billionaire. Appealing to Republicans will be key, according to Thomas Mann of the Brookings Institution.

THOMAS MANN: Democratic members of House and Senate overwhelmingly support various campaign finance reforms. And all the action really has to be on the Republican side.

GOLDSTEIN: Mann says, the Mayday PAC's goal is a long shot. He says, voters don't tend to choose candidates based on their position on campaign finance. And even Lessig himself calls the Mayday PAC goal plausibly crazy. Still, it's worth asking, what do they want if they win? After all, recent changes to campaign finance have been driven more by the courts than by Congress. Lessig says, a first step would be more public funding for elections, possibly in the form of vouchers.

LESSIG: Every registered voter gets a voucher that they could then give to a candidate who agrees to fund his or her campaign with vouchers only and maybe also with small contributions up to a hundred dollars.

GOLDSTEIN: The vouchers would be small - between 50 and $200 - but they'd add up to billions of dollars in every election. It could mean even more money in politics, more Machiavellian political consultants, more negative political ads. He says, he knows all this, and he's okay with it.

LESSIG: I'm not promising utopia. I'm not promising fixing politics so people love it or want their children to marry politicians. All I'm addressing is a tiny slice, but I think the critical first slice to solve, which is the way we fund elections, because the way we fund elections corrupts Congress.

GOLDSTEIN: But to change even this tiny slice, Lawrence Lessig is going to have to raise a lot more money. Jacob Goldstein, NPR News. Transcript provided by NPR, Copyright NPR.